Clean up usage of temp directories in _stage_extra_packages
Clean up usage of temp directories in _stage_extra_packages

* temp_dir is a required parameter, clarified the doc string
* Renamed similarly named tempdir to temp_dir and creates this new
temp directory under the temp_dir. A separate temp directory is
needed for listing only the downloaded resources at this stage.
* Removed the tempdir clean up stage. Caller is giving the tempdir
and responsible for cleaning it. Only caller (stage_job_resources)
already does this.

vikkyrk/incubator-beam,apache/beam,vikkyrk/incubator-beam,chamikaramj/beam,apache/beam,dhalperi/beam,jbonofre/beam,sammcveety/incubator-beam,xsm110/Apache-Beam,jasonkuster/beam,chamikaramj/beam,robertwb/incubator-beam,eljefe6a/incubator-beam,rangadi/beam,wangyum/beam,lukecwik/incubator-beam,ravwojdyla/incubator-beam,chamikaramj/beam,markflyhigh/incubator-beam,chamikaramj/beam,manuzhang/incubator-beam,xsm110/Apache-Beam,staslev/beam,RyanSkraba/beam,tgroh/incubator-beam,amarouni/incubator-beam,apache/beam,rangadi/incubator-beam,staslev/beam,rangadi/beam,jbonofre/beam,robertwb/incubator-beam,manuzhang/beam,RyanSkraba/beam,amitsela/incubator-beam,manuzhang/incubator-beam,lukecwik/incubator-beam,tgroh/beam,iemejia/incubator-beam,vikkyrk/incubator-beam,lukecwik/incubator-beam,tgroh/beam,lukecwik/incubator-beam,lukecwik/incubator-beam,chamikaramj/beam,markflyhigh/incubator-beam,apache/beam,markflyhigh/incubator-beam,RyanSkraba/beam,charlesccychen/beam,amitsela/beam,robertwb/incubator-beam,charlesccychen/incubator-beam,jasonkuster/beam,yk5/beam,markflyhigh/incubator-beam,robertwb/incubator-beam,amarouni/incubator-beam,jasonkuster/beam,chamikaramj/beam,wtanaka/beam,wangyum/beam,apache/beam,lukecwik/incubator-beam,charlesccychen/beam,lukecwik/incubator-beam,wangyum/beam,amitsela/beam,staslev/beam,tgroh/incubator-beam,jbonofre/incubator-beam,apache/beam,mxm/incubator-beam,peihe/incubator-beam,charlesccychen/incubator-beam,apache/beam,xsm110/Apache-Beam,tgroh/beam,wtanaka/beam,robertwb/incubator-beam,RyanSkraba/beam,yk5/beam,mxm/incubator-beam,apache/beam,charlesccychen/beam,rangadi/beam,manuzhang/beam,RyanSkraba/beam,chamikaramj/beam,eljefe6a/incubator-beam,amitsela/incubator-beam,chamikaramj/beam,rangadi/incubator-beam,markflyhigh/incubator-beam,dhalperi/incubator-beam,jbonofre/beam,staslev/incubator-beam,apache/beam,lukecwik/incubator-beam,dhalperi/beam,robertwb/incubator-beam,charlesccychen/beam,dhalperi/incubator-beam,rangadi/beam,chamikaramj/beam,lukecwik/incubator-beam,wtanaka/beam,sammcveety/incubator-beam,manuzhang/beam,charlesccychen/beam,yk5/beam,jasonkuster/incubator-beam,robertwb/incubator-beam,apache/beam,charlesccychen/incubator-beam,chamikaramj/incubator-beam,RyanSkraba/beam,rangadi/beam,rangadi/beam,tgroh/beam,jbonofre/incubator-beam,chamikaramj/beam,ravwojdyla/incubator-beam,rangadi/beam,sammcveety/incubator-beam,chamikaramj/incubator-beam,RyanSkraba/beam,peihe/incubator-beam,jasonkuster/incubator-beam,iemejia/incubator-beam,rangadi/incubator-beam,robertwb/incubator-beam,wangyum/beam,jbonofre/beam,lukecwik/incubator-beam,charlesccychen/beam,staslev/incubator-beam,markflyhigh/incubator-beam,dhalperi/beam,amitsela/beam,peihe/incubator-beam,markflyhigh/incubator-beam,ravwojdyla/incubator-beam,charlesccychen/beam,eljefe6a/incubator-beam,apache/beam,robertwb/incubator-beam,robertwb/incubator-beam